Update on the German source via Ebay; Yep, they are the right ones so the part numbers are ok. The units themselves are made in India (a sticker attached, I've not suddenly developed clairvoyant powers
) The gaskets are black rubber which I assume is right, mine are so old and faded they're a sort of greyish colour.
One thing I would add if anyone is thinking of buying via Ebay, the postage costs more than the actual lamp unit. That's because the guy sends a tracked parcel and it costs the same for one unit as it does for a dozen. I stocked up for the Elan & Europa, for you guys in the US it might be worth considering a group buy ?
Brian